For the convenience of a usage of a user, some of the existing electronic devices are provided with an information input device. For example, a computer is provided with a keyboard, and information input by the user is acquired by acquiring an operation of the user to the button.
However, in the existing electronic device a capacitive touch screen needs to be provided to identify information input by the user. When the user performs an operation to the capacitive touch screen, input information is identified by collecting coordinates for the operation relative to the capacitive touch screen. However, the capacitive touch screen is expensive, thereby resulting in a high manufacturing cost of the electronic device.